But Eric Pratt, the spokesman for the Gun Owners of America, had a different explanation for Reagan's support of an assault weapons ban - senility.

When asked about Reagan's position on gun control during an appearance Wednesday on MSNBC's Andrea Mitchell Reports, Pratt responded that Reagan had only supported gun control measures "in his later years."

Andrea Mitchell: What’s the problem with registering a gun? If you have a bushmaster... first of all, why would you have a bushmaster...

Pratt: President Reagan owned an AR-15.

Mitchell: And he supported gun control. He advocated…

Pratt: In his later years. We have to keep that in account.

Mitchell: In his later years he was almost killed by John Hinckley.

Pratt: But all through his presidency he opposed gun control, that’s my point.

Pratt is wrong on the facts. Reagan signed the Firearm Owners Protection Act into law in 1986, which “banned ownership of any fully automatic rifles that were not already registered on the day the law was signed.”

Regarding handguns, Reagan stated, "This level of violence must be stopped...If the passage of the Brady bill were to result in a reduction of only 10 or 15 percent of those numbers (and it could be a good deal greater), it would be well worth making it the law of the land."

Reagan also wrote an op-ed in the New York Times in 1991 titles "Why I'm for the Brady Bill," expressing support for a seven-day waiting period on handgun purchases. As governor of California, Reagan signed a strict 15-day cooling-off period into law.

In 1994, Reagan joined other former presidents Jimmy Carter and Gerald Ford in a joint letter to the Boston Globesupporting the Assault Weapons Ban, saying, "As a longtime gun owner and supporter of the right to bear arms...I am convinced that the limitations imposed in this bill are absolutely necessary."

Presidential candidate Bernie Sanders addressed an estimated 100,000 supporters at more than 3,500 house parties in all 50 states on Wednesday night, at what is being called the largest campaign event of the 2016 election cycle thus far.